Children who can only speak through computerised aids are being helped to tell jokes through a new "language playground".

Researchers at the universities of Dundee, Aberdeen and Edinburgh have developed a software package called Standup.

The System To Augment Non-speakers' Dialogue Using Puns enables children to use puns to overcome language barriers.

Eight youngsters used the software during a 10-week trial in Glasgow.

The three-year project has been created for children who use speech technology similar to that used by the physicist Stephen Hawking.

The research team said computerised speech aids could restrict the development of a child's language skills, as his or her speech tends to stick to absolute essentials and lack spontaneity.

What do you call a spicy missile? A hot shot!

Standup joke

Speaking children typically use humour to experiment with words and improve their social skills, but those who speak through voice output communication aids are often denied these forms of fun.

Research suggests that limiting communication in this way means the child does not become as fluent, nor as adept at conversation, as children who have no language limitations.

Standup, which was developed with the help of teachers, therapists and adults who use voice output communication aids, allows users to create puns with the software using dictionaries and information about words.

Eight youngsters at Capability Scotland's Corseford School near Glasgow used the system and told jokes like: "What do you call a spicy missile? A hot shot!"

'Novel language'

Dr Graeme Ritchie, of the University of Aberdeen, said: "The Standup software makes simple puns by looking for suitable patterns in the words and phrases which are available to it.

"In this project, the computer acts as a helper to the child, by letting them browse through joke forms and try out words and phrases."

The University of Dundee's Dr Annalu Waller said many people who use communication aids tend to be passive communicators, responding to questions with one or two word answers.